Malicious PDF — malware analysis report

Static analysis result for SHA-256 321ff7febce14efa…

MALICIOUS

PDF

78.3 KB Created: 2021-08-29 22:35:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 3d6e478243018615839752b257f0202f SHA-1: 7fcbf495ce4db789a347fc3905a143ee56ec2c61 SHA-256: 321ff7febce14efa06fc884319d803ad6ae78f77f81e6170d07bf9cd164af74f
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the structure and numerous external links suggest it's designed to lead users to potentially harmful content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://aeronautike.com/userfiles/file/68752106112.pdf In PDF document text
    • http://geonatlife.es//ckfinder/userfiles/files/60475573809.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16080190fec5cf---kudeditimelilojed.pdfIn PDF document text
    • https://behagi.eus/files/galeria/files/solidagugazene.pdfIn PDF document text
    • http://jkohut.pl/file/30013352539.pdfIn PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/13618212720.pdfIn PDF document text
    • http://hindel-relax.ch/ckfinder/userfiles/files/97954679650.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/b4d09a1f7042f3367c441f6e8c629380/nifekaminerofisej.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/gozuxazakabugifujaj.pdfIn PDF document text
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/38143033120.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/54703514348.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/89h927gas2taadk8iomkf8evk5/26660681400.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3433834be---39547202371.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607596c456f28---77180425175.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/figixagejejeze.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/jch9aadh7u406eeh4thj4dtpc9/31384899604.pdfIn PDF document text
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/fegofobedexolubobis.pdfIn PDF document text
    • https://www.haievent.com/wp-content/plugins/super-forms/uploads/php/files/p3kocdni5fubpaktscrg2evmns/86215572038.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/16074b710a3455---vuxaletalarodu.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dbb13bada2---giwepaparifinuxog.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/d9c61b98bcdd4fbc5c926648e23db7c2/netewifexotito.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb386b5cf9---84697361504.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/1c3b137986bddbad3507a9996af5f170/25229362534.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=acca+paper+f8+audit+and+assurance+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE7D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e68f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE68F 16940 bytes
SHA-256: 848ad333c654fbcece92c25767e8d25f9561048eb1e3918a46e07470d49969c0
font_02_sfnt_off00011231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11231 10736 bytes
SHA-256: 35401b2babcd230d96caf521966c62ae3f2506b214cbb47fdd99c34316d479ef